Ornamental Fish Production and Management

4.2.2 Filter media

A number of filter media are available.  The more common ones are given in Table.

Filter media

Sl.No.	Filter Medium	Working	Items removed
1.	Nylon floss	Mechanical	Solid suspended particles
2.	Filter (glass) wool	do	do
3.	Plastic foam	do	do
4.	Sand	do	do
5.	Gravel	do	do
6.	Diatomite (diatomaceous earth)	do	do
7.	Sponge	do	do
8.	Diatom Skeleton	do	do
9.	Activated charcoal	Chemical	(CO2, pH & hardness)
10.	Limestone chips	do	(pH & hardness)
11.	Coral sand	do	do
12.	Peat	do	do
13.	Resin (zeolite)	do	Hardness & NH3

          Infact, all media work mechanically, and biologically if left undisturbed over long period.  In the latter case, all media will be eventually colonized by bacteria.  Plastic, glass and gravel may offer good bed (surface area) for bacteria to grow on.

          Of all the filter media, the cheapest are floss, foam and gravel.  Peat, on the other hand, is not long lasting and needs replacement at quick intervals (as it is quickly exhausted).